Update: *After* completing my online order, I received this info: "Your Order May Take Longer Than Usual. Due to high demand, there may be a delay in preparing or shipping your order. You will receive an email notification when your order status changes. Thank you for your understanding and patience."
Isn't that something they should let customers know *before* they pay? Very underhanded business practice.
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I won't bother going into the details, because I've already spent too long on this purchase (including time spent on the phone with customer service, who eventually told me that I should just abandon my attempts to make the purchase on my phone and try the computer, and if that didn't work, there was nothing else they could do), but the checkout process is seriously flawed. I won't be ordering from this site again. I could have gone to the store 5 or 6 times in the time it took to place the order. More's the fool, me.